Blackboard.



E. L. KRAUS.

BLAGKBOARD.

APPLICATION PILBD JUNE 2, 1911.

Patented May 21, 1912.

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BLAOKBOARD.

APPLIOATION FILED JUNE 2, 1911.

Patented May 21, 1912.

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WITNESSES I INVENTOR g liqZwardLJnua' W m7 Altorney COLUMBIA PLANOORAPHC0" WASHINGTON, D. c.

E. L. KRAUS.

BLAGKBOARD.

APPLICATION FILED JUNE 2, 1911.

1,026,809. Patented May 21, 1912.

3 SHEETS-SHEET 3.

N WITNESSES INVENTOR Z 2 m fqflamey COLUMBIA I'LANOGRAX'H 0-.WAIIIIIIIIIII C.

EDWARD Ii. KRAUS, OF SLATINGTON, PENNSYLVANIA.

BLACKBOARD.

Specification of Letters Patent.

Application filed June 2, 1911. Serial No. 630,897.

To all whom it may concern:

Be it known that I, EDWARD L. KRAUs, a citizen of the United States,residing at Slatington, county of Lehigh, State of Pennsylvania, haveinvented certain new and useful Improvements in Blackboards, of wh1chthe following is a specification, reference being had therein to theaccompanying draw- 111.

This invention relates to certain new and useful improvements inblack-boards, the object being to improve the general construction andto provide a board which can be packed for shipping in such a mannerthat all danger of any of the parts becoming broken is prevented.

Another object of the invention is to provide novel means for connectingthe legs to the frame of the board whereby each leg will have anindependent adjustment in order to allow the legs to adjust themselvesto any unevenness of the floor.

A further object of the invention is to provide a board with adetachable chart case which is exceedingly simple and cheap inconstruction and one which can be readily attached or detached, theattaching means being so positioned in respect to the housings for thechart rolls that all danger of the same being injured in shipping isprevented.

A still further object of the invention is to provide novel means forrotating the chart rolls, said means being capable of being used forlocking the rolls when the blackboard is being shipped.

Other and further objects and advantages of the invention will behereinafter set forth and the novel features thereof defined by theappended claims.

In the drawingsFigure 1 is a perspective view of my improved blackboard;Fig. 2 is a rear elevation partly broken away; Fig. 3 is a verticalsection through the board and chart case; Fig. 4 is a detail rearelevation, the housing being shown in section and one of the rollspartly broken away to show the manner of mounting the spring thereon;Fig. 5 is a detail view showing the manner of securing the chalk tray ina set-up position; Fig. 6 is a detail View showing the chalk tray inposition for shipping; Fig. 7

is a rear elevation part1 broken away of a modification; and Fig 8 1s aside elevation of the same.

Like numerals of reference refer to like parts in the several figures ofthe drawings.

In the drawings, 1 indicates the blackboard proper, 2 the supportinglegs and 3 a detachable chart case. The black board proper comprises apair of side bars 2 having grooved inner edges 3 in which the tenons ofcross-bars 4 and 5 are secured, forming a substantiallyrectangular'frame for the writing surface 6. The extreme ends of thebars 2 are connected together by a cross-bar 7 which is spaced from thecrossbar 5 as clearly shown forming an opening for the chart 8. Thelower cross-bar 4 is provided with transverse slots 9 in its lower edgeinto which are adapted to fit headed pins 10 carried by a chalk tray 11and it will be seen that when said chalk tra is in the position shown inFig. 5, it will be firmly held in position by frictional contact. Thewalls of the slots 9 are enlarged as shown at 12 having a diameterslightly larger than the diameter of the heads of the pins 10 and intowhich the heads are adapted to be forced when the chalk tray 11 isplaced in the position shown in Fi 6 for shipping, the tray beinsubstantially the same thickness as the side bars 2.

The rear faces of the side bars 2 are transversely grooved as shown at13 forming bearings for a tie-rod 14 which is secured therein by plates15, said tie-rod being provided with a head 16 at one end and a wing nut17 at its other end. Mounted on the respective ends of the tie-rod 14are legs 2 which are clamped against the side edges of the side bars 2by the wing nut 17 in such a manner that the legs will be held in theiradjusted position in order to support the black-board at any angledesired. It will be seen that by this construction, each leg has anindependent movement in order to allow it to adjust itself to anyuneveness of the floor.

The chart case 3 comprises a pair of strips 19 carrying blocks 20forming the end walls of housings 21 and 22 which are formed by acontinuous strip of suitable material 23 Patented May 21, 1912.

which is secured over the blocks and to the strips 19 to form thehousings and a central backing 24 for the chart 8. The blocks areprovided with bearings through which extend the trunnions 25 and 26formed on the respective ends of the rollers 27 to which the respectiveends of the chart 8 are secured. The trunnions 26 are provided withhandle portions 28 by which the roll-ers are rotated in order to shiftthe chart from one roll to the other. In order to prevent the unwindingof the chart from the rolls, I provide a tension device which comprisesa coiled spring 29 one end of which is seated in an annular recessformed in the end of the roll carrying the trunnion 26 and the other endis seated in a cup 30 carried by the block insuch a manner that pressurewill be applied to the roller in order to prevent the same fromrotating. The chart case 3 is secured in position on the side bars 2 byscrew eyes 31 passing through washers 32 in such a manner that the samecan be easily attached -or detached, said eyes forming an attachingmeans through which a suitable supporting cord can be passed in order tosuspend the board.

In the modification shown in Figs. 7 and 8, the construction of thechart case is slightly modified by forming uninterrupted end pieces forthe housings and the end pieces 33 are secured against the side bars 2and an open housing is formed at each end by strips 34 which are securedin position by central strips 35 so as to form out of the centralportion of the strips a backing portion 36 for the chart 37. In thisconstruction, the chart rollers 38 and 39 are formed substantially thesame as in the preferred form, the same tension means being employed forpreventing the rolls from un winding. In this construction, I have showntwo forms for holding the rolls when being shipped, the holding meansalso performing the function of a crank for operating the rolls. Theform shown attached to the roll 38 comprises a knob 40 which is securedto roller 39 comprises a screw crank which is mounted in a threaded boreformed in the knob and the angle end is adapted to be seated in a recess46 formed in the side pieces 33 of the chart case and in this case, inorder to disengage the end of the arm from the recess, it is necessaryto draw the knob outwardly thereby compressing the tension spring whichalso performs the function of holding the arm within the recess.

WVhile I have only described the tension means for one roller, it is, ofcourse, understood that each roller is constructed exactly alike and isprovided with the same tension means for holding the roller againstrotationin order to prevent the chart from unwinding. It will also beseen that this tension means performs the function of allowing therollers being moved longitudinally in order to disengage the pivotedcranks from the recesses to release the rollers from locked position. ,8

In the drawings, I have shown and described a detachable chalk tray withheaded rojections co-acting with recesses in the rame of theblack-board, but it is, of course,

understood that the frame could be provided with projections and thetray with recesses for accomplishing the same purpose.

Having described my invention and set forth its merits what I claim anddesire. to secure by Letters Patent is- 1. A black board comprising aframe having a board proper arranged therein and provided with openings,a chalk tray having headed projections fitting in the openings formed inthe frame ofsaid board, and pivoted legs for supporting said frame.

,2. A blackboard comprising a frame formed of side bars and cross-barshaving transverse slots formed in one of the crossbars, and a chalk trayhaving headed pins adapted to fit in said slots when in a set-up orknock-down position.

3. A blackboard having a chart case, rollers mounted in said casecarrying a chart, knobs carried by said rollers and pivoted meanscarried by said knobs for locking said rollers against rotation.

4. A blackboard having a chart case, roll-,

ers mounted in said case carrying a chart, and pivoted members carriedby said rollers for locking the rollers against rotation.

5. A black board having a chart case detachably secured thereto, springpressed rollers mounted in said case, knobs carried by said rollers,pivoted cranks mounted in said knobs, said cranks being capable of beingswung into position to lock said rollers.

6. A blackboard having a chart case, rollers mounted in said chart case,said case having recesses, and pivoted cranks carried by said rollersadapted to fit within said recesses for locking said rollers againstrotat-ion.

7. Ablackboard having adetachable chart case comprising side memberscarrying spaced end pieces, said end pieces and side members beinginclosed by strips to form spaced housings a central supporting portion,and rollers having tension means mounted in said housings carryin achart, knobs carried by said rollers, and pivoted cranks carried by saidknobs.

8. In a blackboard, the combination with a chart case, of rollers havingknobs, and pivoted cranks carried by said knobs capable of being movedin position to rotate said rollers or to lock said rollers against rota-10 tion.

In testimony whereof I aifix my signature in presence of two witnesses.

EDl/VARD L. KRAUS.

Witnesses:

MINNIE REX, MABEL MoYER.

Copies of this patent may be obtained for five cents each, by addressingthe "Commissioner of Patents, Washington, I). G.

